The Breeding Bird Survey (BBS) provides good coverage of the majority of the Common Grackle's breeding population in Canada and is the most reliable source of monitoring data. BBS results indicate the species' population has shown little overall change since the early 1970s. Annual indices demonstrate that numbers decreased until the mid-1990s, levelled off, and then rose slightly after about 2010 (see Canada graph below). Population trends vary somewhat among the various Bird Conservation Regions (BCRs) inhabited by this widespread species, ranging from moderate to large decreases in the areas of highest population density (Lower Great Lakes/St. Lawrence Plain and Atlantic Northern Forest), to an increase in the Prairie Potholes (all BCRs for which there are sufficiently reliable data are shown below). The Common Grackle population is currently at an acceptable level relative to its national population goal. In contrast to the Canadian situation (see Canada graph below), BBS results from throughout North America indicate a large decrease in the continental population.
Additional information on: Breeding Bird Survey (BBS) - Canadian analysis
